Matrix Multiplication

Grade 12 Maths — Matrix Multiplication: 25 practice questions with instant scoring and explanations.

1. Two matrices A (m × n) and B (p × q) can be multiplied as AB if:
2. If A is 2 × 3 and B is 3 × 4, then AB is:
3. Matrix multiplication is:
4. Matrix multiplication is associative: (AB)C = A(BC). This is:
5. If A = [[1, 2], [3, 4]] and B = [[2, 0], [1, 2]], then AB equals:
6. The multiplicative identity for square matrices is:
7. If AI = A (where I is identity), then this property is called:
8. The property A(B + C) = AB + AC for matrices is:
9. If AB = BA = I, then B is called:
10. If A is 3 × 2 and B is 2 × 3, then BA is:
11. The element (AB)ᵢⱼ is computed as:
12. If A² = A, then A is called:
13. For matrix multiplication, A·I = I·A = A demonstrates:
14. If A = [[2, 1], [0, 3]], then A² equals:
15. The number of multiplications needed to compute a 2 × 3 matrix times a 3 × 2 matrix is:
16. If AB = 0 (zero matrix), then:
17. Matrix multiplication is distributive over addition: A(B + C) = AB + AC. This is:
18. If A is 2 × 3 and I is the 3 × 3 identity, then AI equals:
19. The trace of AB equals the trace of BA when both products are defined:
20. If A = [[1, 2]] (row matrix) and B = [[3], [4]] (column matrix), then AB equals:
21. The associative property (AB)C = A(BC) is important for:
22. If A is a 3 × 3 matrix and B is its transpose, then AB is:
23. Matrix multiplication of a 3 × 2 matrix and a 2 × 2 matrix gives:
24. Graph y = |x - 1|
25. Solve 2x² + 3x + 1 = 0